1. Field of the Invention
This invention relates to machines for filling containers and applying caps to close the containers, and more specifically, to inline filling and capping machines where threaded caps are applied to continuously moving containers.
2. Summary of the Invention
Variations in the configurations of containers and closures, in the contents of the containers and in the operation of the closures must all be accommodated for successful high speed filling and capping operations. Capping has usually been accomplished by either chuck-type capping machines in which the caps are grasped and twisted onto a filled container, or by capping machines employing multiple pairs of rotating discs which engage opposite sides of a cap and twist it in a closing direction. Chuck-type capping machines require a different chuck for each size of cap which can be costly to use if many sizes of caps are processed because of the storage of the chucks and the time required for installation and adjustment. Disc-type capping machines require multiple arrangement of disc drives which are costly to acquire, maintain and adjust.
It is an object of the invention to provide a capping machine in which caps are twisted to a closed position by belts engaging opposite sides of the cap.
It is a further object of the invention to provide a capping machine which employs cap engaging belts to exert a twisting force to apply caps to filled containers continuously at a high rate of speed. a cap by regulating the speed and time of contact and release of belts with the cap with such variables being adjustable without interrupting movement of the filling and capping line.
Another object of the invention is to provide a capping machine that will accommodate an infinite variety of cap shapes and materials with the associated variations in closing force requirements.
The objects of the invention are accomplished by a programmable capping machine in which caps are delivered to continuously moving containers after they have been filled to place the caps on top of the containers where they are engaged by the capping machine to apply a twisting action to move the caps to a closed position. This is all accomplished at a very high rate of speed, to the order of 200 containers per minute. The capping action is accomplished by employing a pair of belts having adjacent flights engaging opposite sides of the caps with the flights traveling in opposite directions to twist the caps to a closed position. The twisting action of the belts is modified by oscillating load applying and releasing shoes into engagement with the belts to move the cap engaging flights into and out of engagement with the caps. In addition to the speed of the belts, the duration of belt engagement with the caps and the duration of the release of the belts from the caps are programmable so that a wide variety of conditions can be accommodated. Also, the maximum torque that can be applied to a cap is regulated by a clutch which is adjustable and programmable.